- It represents about 15 % of the cases. It is never congenital.
- Lined by columnar epithelium, discharges mucus and is a site of recurrent infection.
Thyroglossal cyst locations:Related to the thyroglossal duct
- Subhyoid (M/C site)
- On thyroid cartilage (2nd M/C site)
- Beneath foramen caecum
- Mouth floor
- It moves up with swallowing and with protrusion of the tongue.
- Hood sign: Opening of fistula is indrawn and overlaid by fold of skin
- Semilunar sign: Peculiar crescentic appearance
- Radioisotope study
Sistrunk operation (prevents recurrence)Excision of cyst + full tract up to foramen caecum + central part of hyoid bone